There is known a coating thickness control system that performs a laminate process for coating a base material, such as paper, aluminum foil, and plastic, with a resin. A T-die (mold), which controls the flow rate of a resin plasticized and melted by an extruder, is used in this coating thickness control system. A structure disclosed in, for example, PTL 1 is known as a structure that adjusts the flow rate of a molten resin at the T-die by a pneumatic driving method.
A mechanism, which includes an actuator including a lever and a push bolt, is disclosed in PTL 1. The lever is provided on a first T-die body of a T-die body that includes first and second T-die bodies, and bellows are fixed to the upper portion of the lever. The first T-die body includes a flexible lip part at the lower portion thereof, and the second T-die body includes a stationary lip part at the lower portion thereof. The lower portion of the lever is pivotally supported on the first T-die body. The push bolt is provided below a pivot. Further, compressed air is sent to the bellows, the bellows are expanded, the end portion of the push bolt provided below the pivot comes into contact with the flexible lip part, and the lever is rotated in a direction where the flexible lip part is pressed. Accordingly, a gap between the stationary lip part and the flexible lip part is adjusted.